Hermetically sealed tin



1935b A. H. DOWNES-SHAW ET AL 2,023,341

' HERMETICALLY SEALED TIN Filed Aug. 28, 1934 3 Sheets-Sheet l 'I'I'II/IIIIIIIIIIIIIIl,

INVENTORS ARCHIBALD H. DOWNESSHQW ALEXANDER S. RUSSELL ARTHUR L. 5TUCH BE RY Dec. 3, 1935. v A. H. DOWNES-SHAW ET AL 2,023,341

HERMETICALLY SEALED TIN Filed Aug. 28, 1934 3 Sheets-Sheet 2 FIG. 12.

III/Ill/I/IIIIIII/II/IIIII/lIlllI/ INVENTOES AECHIBALD H. DOWNES-SHAW ALEXANDER S. RUSSELL AE'THUR LSTUCHBERY b i'kez'r offer/rays Dec. 3, 1935. A. H. DOWNES-SHAW ET AL 2,923,341

HERMETICALLY SEALED TIN Filed Aug. 28, 1934 3 Sheets-Sheet 3 IG. 0. 25 F I FIGJP.

INVENTORS ARCHIBALD' H. DOWNES'SHAW ALEXANDER 5. RUSSELL ARTHUE L. STUCH BERY by flee/r a/fanrys 2 1 Mag the order of a thousandth of an inch or so).

Patented Dec. 3, 1935 UNITED STATES PATENT OFFICE HERMETICALLY SEALED TIN company Application August 28, 1934, Serial No. 741,862 In Great Britain September 8, 1933 15 Claims.

This invention relates to tin containers of the type in which the tin is adapted to be hermetically sealed by subjecting the interior to a vacuum or partial vacuum, while on the release of the vacuum the lid may readily be pulled off by hand without the use of tools or levers.

The object of this invention is to provide a simple construction of tin of the above type which, although the lid is readily removable without tools after the release of the vacuum, yet permits the lid to remain secured to the body after the release of the vacuum so as to prevent its accidental removal therefrom.

The present invention comprises a tin adapted to be hermetically sealed in which the periphery of the body portion at or near its open end engages against a sealing material in a corresponding portion of the lid to effect an hermetic seal when the inside of the tin is subjected to a vacuum or partial vacuum, wherein a shallow wall of the lid is secured to the body by means of a bead or the like at or near the periphery of the one engaging with indentations or pips at or near the periphery of the other, the body being deformable during engagement and disengagement.

The present invention also comprises a tin adapted to be hermetically sealed in which the body of the tin is formed at or near its open end with a bead or the like around its periphery, indentations or pips being provided upon a shallow wall of the lid to engage under the said bead, said indentations or pips being the sole mechanical means for securing the lid against accidental displacement from the body when the vacuum is destroyed.

The tin is eminently adapted for mass production since its functioning will not be adversely aifected by small variations in dimensions (of The indentations or pips, for example three, constitute spaced engagement points between the lid and body, and the periphery of the body portion is free to be distorted slightly from its original outline to ensure the ready removal of the lid by hand when desired.

It will be understood that the maximum benefit of this invention is attained when the engaging points are nearest to the mouth of the body portion.

It follows that the depending portion of the lid upon which the engaging means are formed should therefore be shallow thus avoiding frictional engagement except at the points provided and enabling the lid to be levered off by the minimum of effort. A flange, preferably provided at the edge of this depending portion of the lid provides a convenient means for the application of this leverage.

Preferably a small perforation or pinhole is provided on the body or lid of the tin, said hole being covered by a sealing patch formed for instance from sheet rubber, the removal of which destroys the vacuum.

The body of the tin may be pressed from a sheet of metal to have the form of a shallow cylindrical dish, the metal at the top edge of the dish being turned inwards to form a circular bead around its periphery. The lid may be formed from a metal disc which is pressed to provide an annular groove, and a number of pips or indentations (for instance three) are formed in the metal constituting the inside wall of said annular groove, said indentations extending outwards towards the space constituting the groove. A sealing material, for instance, a rubber ring or a coagulating solution, is located in the annular groove in the lid, and after the tin has been filled with the desired contents, for instance tobacco, the lid is placed over the body so that the inwardly turned circular bead presses against the rubber or other sealing material in the annular groove in the lid.

The air is then exhausted from the tin in any convenient manner, for instance by placing the tin in a chamber subjected to vacuum, and after the tin-is removed from the vacuumizing chamber the pressure of the air thereon maintains the hermetic seal.

The lid may alternatively be bent so as to provide an annular groove at the top of the lid and thus an upstanding wall on the bottom. The outside face of the wall is substantially vertical (1. e. at right angles to the plane of the disc) While the inside edge is sloping. The two edges meet at a relatively sharp radius to form the ridge. The lid is placed under a punching tool comprising a number (for instance three) of relatively blunt edges, which act on the top of the ridge said edges extending at right angles to the ridge, i. e. radially.

These blunt edges of the punching tool depress the metal of the ridge by one or two hundredths of an inch, and thereby cause the vertical face of the wall in the immediate neighbourhood to be bulged out somewhat, for instance about 4 or 5 thousandths of an inch.

The lid with a ridge as just described may also be formed by placing it under a pressing tool comprising a number (for instance three) of relatively blunt wedges, which press against the slanting inside wall, particularly near the top towards the ridge. These wedges of the press tool press in the metal of the inside sloping wall near the ridge so as to make it concave for a slight extent and also force outwardly the ridge thereof into a curve of sharper radius than the remainder of the ridge, the maximum deformation in the centre of the curve being about l/lOOth of an inch. The ridge is thereby decreased in width somewhat but nevertheless acts to force outwardly the outer vertical wall near the ridge and form bulges thereon to the extent of about three to four thousandths of an inch.

The body of the tin may be formed with an inwardly extending ridge at its open end, for instance by forming an inwardly turned peripheral bead there. When the lid is placed in position on the body, the aforesaid bulges on the vertical face spring over the inwardly extending ridge on the body, and hold the lid in place, while permitting it to be sprung open when desired.

The tin may be of cylindrical form, or alternatively its plan view instead of being circular may be oval or rectangular.

Various constructional forms of tin in accordance with the present invention are diagrammatically indicated in the accompanying drawings in which:-

Figure 1 is a cross section of one form of tin in accordance with the invention.

Figure 2 is an underneath view of the lid shown in Figure 1.

Figure 3 is a partial cross section of the tin, on a larger scale, taken on a vertical plane corresponding to the line 33 of Figure 2.

Figure 4 shows an underneath view of a modified type of lid.

Figure 5 is a partial cross-section, on a larger scale, of a tin having this lid and taken on a vertical plane corresponding to the line 55 of Figure 4.

Figure 6 is a cross section of a tin showing a further modification of the lid.

Figure 7 is an underneath view of the lid shown in Figure 6.

Figure 8 is a cross section of the tin, to an enlarged scale, taken on a vertical plane corresponding to the line 8-8 of Figure 7.

Figure 9 is a cross section of a tin of rectangular shape.

Figure 10 is an underneath view of the lid shown in Figure 9.

Figures 11 and 12 are cross sections of further modifications.

Referring to Figures 1, 2 and 3 of the drawings:,The tin comprises a cylindrical body portion I, which is provided with an inwardly turned bead 2 around its periphery. The bottom of the tin as shown has a large circular depressed portion 3 extending almost to its edge 4 and at the centre of this portion 3 it is further depressed at 5 and said portion 5 is perforated at 6. The perforation 6 is covered by a patch 1, which may be of rubber. The lid of the tin is shaped to provide a groove 8 in which is located a sealing material S, the exterior of the edge of the lid being beaded at H].

The metal wall portion ll constituting the inside of the groove 8, is indented at points l2, I3 and I4, see Figure 2, so as to provide pips or indentations as indicated by l5, see Figure 3.

In use, the tin after being filled with its contents, for instance, tobacco, is vacuumized, whereby the pressure of the air outside forces the lid tightly on the body and presses the sealing material 9 between the bead 2 of the body and the groove 8 of the lid so as to form a hermetic seal.

When it is desired to obtain access to the contents, the patch I is peeled OE and the vacuum is destroyed by reason of the air entering through the perforation 6. The lid may now be pulled off as it is then only held in engagement by reason of the pips or indentations l2, l3 and 14 engaging with the bead 2 and its removal will only 10 necessitate a slight spring action in the wall of the body. This spring action by deforming the periphery of the body portion out of its original shape, moves the parts of the periphery or bead adjacent the pips or indentations l2, l3, and I4 15 radially outwards, such displacement involving the inward radial displacement of the remaining portions of the periphery or bead. The parts are so dimensioned that without these pips the bead 2 would be a loose fit within the groove 8 so that if turned upside down the lid would fall off except for any slight adhesion of the sealing material.

When the lid is replaced the pips l2, I3 and I4 will engage again with the bead 2 and thus retain the lid in position with a force that is suflicient to prevent the lid from becoming detached when the tin is carried in the pocket, but it is not such as to prevent the ready removal of the lid by hand when desired.

Interengagement of the pips with that part of the bead lying beyond the point of maximum thickness, in conjunction with the sealing material 9 facilitates a substantially airtight junction between lid and body after the vacuum has been destroyed.

If desired the perforation 6 and patch 1 may be provided on the lid instead of on the body portion.

In the form of tin shown in Figures 4 and 5, the shape of the lid is partly modified and the pips are formed in a different manner. In this case the part of the lid adjacent andinterior to the sealing material 9 is shaped to provide a groove It on the upper or exterior surface of the lid, and the downwardly extending ridge ll, which is necessarily associated with such exterior groove [6, is pressed in, (i. e. upwardly) at spaced points l8, l 9 and 2:), see Figure 4, such depression of the ridge causing the lower part of the outer wall 2| of the ridge to be moved outwardly a slight distance, as indicated at 22 of Figure 5, such deformation being transverse to the main deformation, and thus providing indentations which engage underneath the thickest part of the bead 2 of the body of the tin. In this case the body of the tin is formed in the same way as in Figures 1 to 3 and its operation is similar.

Figures 6, '7 and 8 indicate a still further method of forming the indentations. In these figures the lid is formed with a groove E6 on its upper or exterior surface the same way as in Figures 4 and 5, but the indentations, instead of being formed by depressing the ridge ll upwardly, are formed by depressing the inner wall 24 outward- 5 ly into more or less half moon shaped portions 25, 26 and 21 (Figure '7) Such deformation will cause the lower part of the outer wall of the ridge to be deformed outwardly a slight distance, as indicated at 35 in Figure 8, thus providing the indentations that engage under the thickest part of the bead 2 of the body portion. In other respects the tin is formed in the same way and operates similarly to the examples previously described.

Figures 9 and .10 show a substantially rectangular form of tin and in this case the indentations 25, 26 and 21 are formed in substantially the same way as in Figures 7 and 8, i. e. by depressing the inner wall 24 of the ridge outwardly. In this case however the ridge and the corresponding groove I E on the exterior surface of the lid, instead of being circular in outline, take the form of a rectangle with rounded corners.

With tins of this shape opening will be facilitated by taking advantage of the hinging action which is consequent upon the engagement between the pips or indentations and the body portion at two opposite sides of the tin. A slight deformation of the body portion adjacent to the engagement with the lid provided by the indentation 25 will release the lid upon this side, the indentations 26 and 21 becoming disengaged on hinging the lid about the corresponding edge of the body portion.

Figure 11 shows a cross section of a modified form of lid in which, instead of the sealing material 9 being supported in a groove of the lid, the lid is shaped to provide a peripheral ledge 28 with a downwardly extending cylindrical portion 29 adjacent and interior thereto. At the bottom of this portion 29 a certain number of pips, indicated by 30, are provided. This tin works in the same way as those previously described, the only difference being that the sealing material 9 is pressed into contact with the bead 2 of the body part by the peripheral ledge 28 of the lid. The pips 30 act in the same way to provide a slight retaining action between the lid and body.

In the modification shown in Figure 12, the body is provided with an internal bead 2, and an external groove 3| is formed in the vertical wall I of the body thus providing a shoulder 32 to the bead. A shallow downwardly extending outer wall or skirt 33 formed on the lid is indented as at 34 in about three places to engage with said shoulder 32. The top of the lid is made nearly fiat, thus avoiding the relatively large external groove which may introduce a source vof weakness, in that tins with such external groove may collapse if subjected to a very high vacuum.

In the examples shown in the drawings the body of the tin is formed with a bead of substantially circular cross section, but it is understood that beads of other shapes may be used.

In all the modifications shown in the drawings, the body portion is shallow and intended to be pressed out from metal plate. It will be understood however that the invention extends to deep tins and if desired the deep body may be formed by building up. For instance the body may consist of a cylindrical part formed of sheet metal which is joined together along a generating line of the cylinder, the bottom of the tin being provided by a separate plate portion secured thereto. The mouth portion may be constituted by a pressed metal ring which provides the bead 2 at the open end of the tin, or alternatively the bead may be formed direct on the cylindrical part above mentioned. Such form of tin is suitable for containing cigarettes.

The invention has been illustrated and described with reference to a body portion having an inwardly turned bead. If it is desired to utilize a body portion with an outwardly turned bead, the pips or indentations will be so positioned as to engage therewith.

It will be further understood that the purposes of this invention can be achieved by positioning the pips or indentations upon the body portion of the tin instead of in the lid. We havefound however in practice that it is both simpler and cheaper to position the same in the lid instead of in the body.

What we claim is:

1. A tin of the type hereinbefore referred to, in which the periphery of the body portion at or near its open end engages against a sealing material in a corresponding portion of the lid to effect an hermetic seal, when the inside of the tin is subjected to a vacuum or partial vacuum, wherein a continuous shallow depending wall adjacent the edge of the lid is secured to the body by means of a bead or the like at or near the periphery of the one engaging with indentations or pips at or near the periphery of the other, the body being deformable during engagement and disengagement.

2. A tin of the type hereinbefore referred to,

in which the body of the tin is formed at or near its open end with a bead or the like around its periphery, indentations or pips being provided upon a continuous shallow depending wall adjacent the edge of the lid to engage under the said bead, said indentations or pips being the sole mechanical means for securing the lid against accidental displacement from the body when the vacuum is destroyed. v

3. A tin according to claim 1 in which a ridge is formed on the underside of the lid adjacent to [u and interior to the sealing material, the said ridge being deformed at spaced joints so as to provide the indentations, or pips that engage with the body portion.

4. A tin as claimed in claim 1, in which the wall is pressed at spaced points to provide the indentations that engage with the body portion.

5. A tin as claimed in claim 1, in which when the tin is closed the indentations or pips are engaged beyond the thickest part of the bead so that the removal of the lid necessitates an initial tightening action between the lid and the body portion.

6. A tin as claimed in claim 5, in which when the lid is replaced after the vacuum is destroyed, the engagement of the indentations or pips with the lower part of the bead forces the lid and body together to secure in conjunction with the sealing material, a substantially airtight junction.

'7. In combination, a tin container and a loosely fitting lid provided with rigid pips to clip the lid against accidental displacement constructed arranged and adapted for operation substantially as described with reference to the accompanying drawings.

8. A tin of the type hereinbefore referred to, in which the periphery of the body portion at or near its open end engages against a sealing material in a corresponding portion of the lid to effect an hermetic seal, when the inside of the tin is subjected to a vacuum or partial vacuum, wherein means are provided for releasing said vacuum or partial vacuum before the lid is removed, and wherein a continuous shallow depending wall adjacent the edge of the lid is secured to the body by means of a bead or the like at or near the periphery of the one engaging with indentations or pips at or near the periphery of the other, the body being deformable during engagement and disengagement.

9. Vacuum sealed tin having a covered aperture for releasing the vacuum, in which the body of the tin is formed at or near its open end with a bead or the like around its periphery, indentations or pips being provided upon a continuous shallow depending wall adjacent the edge of the lid to engage under the said bead, said indentations or pips being the sole mechanical means for securing the lid against accidental displacements from the body when the vacuum is destroyed.

10. A tin of the type hereinbefore referred to, in which the periphery of the body portion at or near its open end engages against a sealing material in corresponding portion of the lid and a patch is provided over an aperture, both to effect an hermetic seal, when the inside of the tin is subjected to a vacuum or partial vacuum, wherein a continuous shallow depending wall adjacent the edge of the lid is secured to the body by means of a bead or the like at or near the periphery of the body engaging with indentations or pips at or near the periphery of the lid, the body being deformable during engagement and disengagement.

11. Vacuum sealed tin comprising a lid portion and a body portion, one of said portions having a bead around its periphery at or near its open end, the other of said portions having a gasket cooperating with said bead, said tin having a small aperture, a sealing patch covering said aperture and removable to release the vacuum, in combination with means for securing said lid against accidental displacement when said patch is removed, said means comprising solely projections on the other portion adapted to engage under said bead.

12. A tin of the type hereinbefore referred to, in which the periphery of the body portion at or near its open end engages against a sealing material in a corresponding portion of the lid to efiect an hermetic seal, when the inside of the tin is subjected to a vacuum or partial vacuum, wherein there is provided a sealing patch covering a small perforation or pinhole in the body or lid of the tin to facilitate the destruction of the vacuum, and wherein a continuous shallow depending wall adjacent the edge of the lid is secured to the body by means of a bead or the like at or near the periphery of the one engaging with indentations or pips at or near the periphery of the other, the body being deformable during engagement and disengagement.

13. A tin of the type hereinbefore referred to, in which the body of the tin is formed at or near its open end with a bead or the like around its periphery, indentations or pips being provided upon a shallow wall adjacent the edge of the lid to engage under the said head, the inside of said tin being adapted to be subjected to a vacuum or partial vacuum and provided with a sealing patch covering a small perforation or pinhole in the body or lid of the tin to facilitate the destruction of the vacuum, and said indentations or pips being the sole mechanical means for securing the lid against accidental displacement from the body when the vacuum is destroyed.

14. A two-part sheet metal container, one of said parts having a beaded edge and the other of said parts being shaped to form a mating peripheral portion provided with a sealing gasket bearing against said beaded edge when the parts are pressed toward one another, said latter part being further provided with spaced projections or pips adapted to engage said bead beyond the thickest part thereof in order to hold the two parts of the container together with a snap engagement, the fit between the two parts of the container being loose except for the engagement of the pips and gasket with the head.

15. A two-part sheet metal container, one of said parts having a beaded edge and the other of said parts being shaped to form a mating peripheral portion provided with a sealing gasket bearing against said beaded edge when the parts are pressed toward one another, said latter part being further provided with spaced projections or pips adapted to engage said bead beyond the the container.

ARCHIBALD HAVERGAL DOWNES-SHAW'. ALEXANDER SCOTT RUSSELL. ARTHUR LESLIE STUCHBERY. 

